Electrical stop control for knitting machines



June 6, 1967 L. E. RICHARDS ETAL 3,323,334

ELECTRICAL STOP CONTROL FOR KNITTING MACHINES Filed April 22. 1965 2 Sheets-Sheet 1 INVENTORJ A. fi/c'fiards, 7. Bum 941s", H. St een if I'KQ/V/keeler 07? a-zwaz'w xzr ATTORNEY) June 6, 1967 1.. E. RICHARDS ETAL 3,

ELECTRICAL STOP CONTROL FOR KNiTTING MACHINES Filed April 22, 1965 2 Sheets-Sheet 2 mpas, b. View; 44/140. Wfieeler Lawrence E. Richards, Rte. 3; Troy United States Patent 3,323,334 ELECTRICAL STOP CONTROL FOR KNITTING MACHINES D. Bumpas, 1712 Tate St.; Harry I. Steen, 1523 Cruise St.; and Watt 0. Wheeler, 1508 Tate St., all of Corinth, Miss. 38834 Filed Apr. 22, 1965. Ser. No. 450,093 3 Claims. (Cl. 66166) This invention relates to apparatus and equipment which can be attached to a conventional machine utilized in the production of apparel for controlling the operation 1 of such machine.

The invention relates particularly to ladies hosiery and apparatus which can be attached to a conventional circular knitting machine and which will stop operation of the machine to prevent damage to the machine or the hosiery when the machine malfunctions.

Heretofore hosiery has been knit on a circular knitting machie of conventional construction which included a cylinder having a plurality of independent needles, :1 cup ,for applying tension on the hosiery being knit, a fabric fabric tube and a blast of air under pressure is directedacross the top of the cup and the completed stocking is released therefrom after which the stocking is blown up through the fabric tube into the basket. During its travel through the fabric tube, the stocking engages a stop motion switch and closes a circuit to permit the machine tocontinue to operate. If the stocking does not release from the cup and does not extend high enough in the fabric tube to trip the stop motion switch, then the electric stop motion circuit would immediately stop the machine.

On occasion, the top of the stocking has not released from the cup, the toe portion has blown up the fabric tube a distance sufficient to trip the stop motion switch and all the conditions for continued operation of the machine have been fulfilled. Under these conditions, the cup is jacked up into knitting position to engage thenext stocking which is already in the process of being formed. This movement of the cup destroys the stocking which has been completed as well as the stocking being former and has caused damage to the cylinder and needles of the machine.

It is an object of the invention to provide a safety switch which will be actuated to stop the knitting machine when the cup malfunctions.

Another object of the invention is to provide a relatively simple, inexpensive, automatic safety switch for a knitting machine which is actuated by a completed stocking to stop the machine when portions of the machine malfunction.

Other objects and advantages of the invention will be apparent from the following description considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view illustrating one application of the invention applied to a circular knitting machine;

FIG. 2, an enlarged section along the line 2-2 of FIG. 1;

FIG. 3, an enlarged perspective of the safety switch;

FIG. 4, a side elevation illustrating the normal operation of a stocking being blown up the fabric tube;

FIG. 5, a view similar to FIG. 4 illustrating 2. malfunction of the fabric cup; and

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FIG. 6, a view similar to FIGS. 4 and 5 illustrating the operation of the invention.

Briefly stated the present invention is a safety switch which can be applied to a conventional circular knitting machine and adapted to stop such machine when a portion thereof malfunctions. The invention includes one or more fingers carried by a rod which is pivotally mounted on the machine. The fingers extend into the bell mouth of a fabric tube in a position to be engaged by a completed stocking so that if the cup mechanism malfunctions and does not release the completed stocking, such stocking will engage at least one of the fingers when the cup is raised. Engagement of the fingers by the stocking will rotate the rod and cause a short circuit in the machine and thereby stop all operations.

With continued reference to the drawings, a conventional circular knitting machine 10 has a frame 11 and a cup tube 12. A hollow cup 13 is mounted for vertical movement in the cup tube 12 and such cup is provided with a top 14 mounted on a cup shaft 15. The top 14 is adapted to be raised above the cup and the top portion of a stocking 16 being knitted is inserted therein after which the top is lowered to clamp the stocking and to apply tension thereto. During the knitting process the cup will be lowered to retain a tension on the stocking until the stocking is completed. When the stocking has been completed, the feed yarn is severed so that the stocking will fall onto the top of the cup after which the cup will be lowered until the top 14 is substantially in alignment with a fabric tube 17 having a bell mouth 18 on itslower end disposed adjacent to an opening 19 in the cup tube 12. In this position a cup opening mechanism 20 located below the cup tube 12 will raise the cup shaft 15 and the top 14 and simultaneously air under pressure from a blow-out air tube 21 will be directed across the cup tube 12 and into the fabric tube 17.

Normally the stocking 16 will be released from the cup 13 and will be blown up through the fabric tube 17 into a basket 22 at the top thereof. Such basket is open at the top with a wide mesh or screen 23 across the open end to prevent the stocking from being blown out of the basket. During the upward travel of the stocking, it will engage a stop motion lever 24 which extends across the vfabric tube and is pivotally mounted at one end on a If a stocking which has been completed is not released from the cup 13 and does not travel up the fabric tube 17, the stop motion circuit will not be completed by movement of the stop motion lever 24 and the machine will immediately stop. If one end of the completed stocking fails to release from the cup 13 and the opposite end is moved up the fabric tube a distance sufficient to trip the stop motion lever, then the machine will continue to function even though the completed stocking is still held by the cup. As soon as the stop motion lever has been tripped, the cup 13 is again raised to engage the top portion or welt of the next stocking which is in the process of being formed.

In order to prevent damage to the completed stocking, the stocking being formed or the needles or other mechanism of the machine in the event that the stop motion lever has been actuated while a completed stocking is still held by the cup, the present invention includes a pair of brackets 27 and 28 mounted on a support member 29 which supports the lower end of the fabric tube 17. A bar 30 is disposed between the brackets 27 and 28 and such bar is rotatably connected to the bracket 28 by a screw or other fastener 31 at one end and is rotatably connected at its opposite end to the bracket 27 by a 'bar 3 32 having a reduced threaded extremity 33. The opposite end of the bar 32 is provided with a drilled recess 35 for the reception of one end of an L-shaped rod member 36 which is fixed in position by a set screw 37 for a purpose which will be described later. The bar 30 has a plurality 'of spaced openings 38 which slideably receive hookshaped fingers or tines 39 held in fixed adjusted position within the bar 30 by set screws 40. An additional opening 41 extends through the bar 30 and is adapted to slideably receive an L-shaped stop member 42 held in fixed adjusted position by a set screw 43.

Normally the fingers 39 extend over the open end of the bell mouth 18 of the fabric tube and the free ends of such fingers are disposed in alignment with the interior of the fabric tube 17. In order to maintain the fingers 39 in normal operating position, a spring 44 is connected at one end to the stop member 42 andconnected at the opposite end to a fastener 45 carried by the bracket 28. The tension on the spring 45 is relatively light and is sufficient only to maintain the stop member 42 against the bracket 28 during normal operation of the machine.

An L-shaped member 48 is connected by screws or other fasteners 49 to an insulating block 50 which in turn is connected by fasteners 51 to the frame 11. The L- shaped member 48 is connected by an electrical conductor 52 to the cut-off switch of the machine and such L-shaped the cup should malfunction and not release the stocking and the stocking is long enough to trip the stop motion lever, the machine will continue to operate and the cup '13 will again be raised to engage the next succeeding stocking. In this event, when the cup is raised as illustrated in FIG. 6 the completed stocking will engage at least one of the fingers 39 and will cause the bar 30 to be rotated against the tension of the spring 44 until the L-shaped member 36 engages the L-shaped member 48 and causes a circuit to short out the machine before damage can be done to the completed stocking, or the stocking being knit or the elements of the knitting machine.

It will be apparent from the above that a relatively simple safety cut-off device has been provided for a conventional circular knitting machine which will cause 1 the machine to stop in the event that the cup malfunctions and fails to release a completed stocking.

It will be obvious to one skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is illustrated in the drawing and described in the specification, but only as indicated in the accompanying claims.

What is claimed is:

1. The combination of a circular knitting machine for tubular articles and a safety stop motion mechanism for stopping the machine upon the malfunction thereof, said machine including a cup tube, a cup mounted for generally vertical reciprocation within said cup tube, said cup adapted to engage a tubular article during the knitting process and be lowered to apply tension thereto and adapted to release said article upon the completion thereof, a fabric tube located adjacent to said cup t-ube, means for discharging said article through said fabric tube, said safety stop motion mechanism comprising bar means pivotally mounted on said fabric tube adjacent to said cup tube, at least one finger carried by said bar means and having one end disposed in a predetermined position in the path of travel of said article through said fabric tube but permitting said article to pass, and switch means carried by said bar means for interrupting the flow of electrical energy to said machine when said article is not released by the cup during the raising thereof and engages the finger to pivot said bar means and actuate said switch means.

2. The structure of claim 1 including means for resiliently maintaining said one end of said finger in said predetermined position.

3. The combination of a circular knitting machine for knitting tubular articles and a safety stop mechanism for stopping the machine upon the malfunction thereof, said machine comprising a cup tube for receiving said articles during the knitting thereof, a cup mounted for generally vertical reciprocation within said cup tube, said cup adapted to engage a tubular article during the knitting process and be lowered to apply tension thereto and adapted to release said article upon the completion thereof, a fabric tube having one end located adjacent to said cup tube, means for discharging said article from said cup tube through said fabric tube when said article is completed, said safety stop mechanism including at least one finger pivotally mounted on said fabric tube adjacent to said cup tube, said finger having one end disposed in a predetermined position overlying said end of the fabric tube, and switch means carried by said finger for interrupting the flow of electrical energy to said machine, whereby an article remaining in said cup tube during the raising of the cup will engage said finger and move said switch means to stop said knitting machine.

References Cited UNITED STATES PATENTS ROBERT R. MACKEY, Primary Exlaminer. 

1. THE COMBINATION OF A CIRCULAR KNITTING MACHINE FOR TUBULAR ARTICLES AND A SAFETY STOP MOTION MECHANISM FOR STOPPING THE MACHINE UPON THE MALFUNCTION THEREOF, SAID MACHINE INCLUDING A CUP TUBE, A CUP MOUNTED FOR GENERALLY VERTICAL RECIPROCATION WITHIN SAID CUP TUBE, SAID CUP ADAPTED TO ENGAGE A TUBULAR ARTICLE DURING THE KNITTING PROCESS AND BE LOWERED TO APPLY TENSION THERETO AND ADAPTED TO RELEASE SAID ARTICLE UPON THE COMPLETION THEREOF, A FABRIC TUBE LOCATED ADJACENT TO SAID CUP TUBE, MEANS FOR DISCHARGING SAID ARTICLE THROUGH SAID FABRIC TUBE, SAID SAFETY STOP MOTION MECHANISM COMPRISING BAR MEANS PIVOTALLY MOUNTED ON SAID FABRIC TUBE ADJACENT TO SAID CUP TUBE, AT LEAST ONE FINGER CARRIED BY SAID BAR MEANS AND HAVING ONE END DISPOSED IN A PREDETERMINED POSITION IN THE PATH OF TRAVEL OF SAID ARTICLE THROUGH SAID FABRIC TUBE BUT PERMITTING SAID ARTICLE TO PASS, AND SWITCH MEANS CARRIED BY SAID BAR MEANS FOR INTERRUPTING THE FLOW OF ELECTRICAL ENERGY TO SAID MACHINE WHEN SAID ARTICLE IS NOT RELEASED BY THE CUP DURING THE RAISING THEREOF AND ENGAGES THE FINGER TO PIVOT SAID BAR MEANS AND ACTUATE SAID SWITCH MEANS. 